Subway to serve up avocado

Subway will add avocado as a premium seasonal topping for its sandwiches at its 22,000 locations across the United States starting next week, the chain said Friday.

The chain said the fruit would be promoted in several limited-time offers this summer: a turkey and bacon avocado sub; a steak, egg and cheese with avocado for breakfast; a Subway Club with avocado; and a BLT with avocado.

Customer also can add avocado to any regular sub for 50 cents for a 6-inch sandwich and $1 for